The present invention relates to angle measuring devices.
One of such angle measuring devices is disclosed for example in the German patent document DE-U-89 02987.9. In this measuring device two legs are provided which are turnable relative to one another about a joint turning axis, and they are coupled with one another through a potentiometer which measures an angle enclosed between the two legs. Due to the contact of the slider and resistance track of the potentiometer, during a long service time undesired wear can occur. Moreover, the potentiometric measurement of the angle is connected with errors located over a desired angle resolution in the region of 0.1.degree..
Another angle measuring device is disclosed in the German patent document DE 297 03 041 U1. Here the two rotatively coupled discs are driven in rotation and cooperate each with a leg-fixed sensor. The drive shaft and the sensors are supported in this angle measuring device on different legs, which provides an increased measuring accuracy. The provision of the two discs with the associated sensor means is however expensive and complicated to manufacture. The substantial space which is required for the known measuring device makes it impossible the accommodation of the drive of the disc inside a turning link of the leg. Thereby the taking down an angle adjusted between the legs or the abutment of the leg on an angle to be determined is difficult. The opposite support of the leg is performed by three roller bearings arranged in a plane, which can not guarantee a sufficient concentricity of the legs during the manufacture.